Hotswapagent without DCEVM

[Marian Koncek]

Hi, i am working on a thesis about decompilation / recompilation of java bytecode and its reloading into a running java process, i have had success when reloading the bytecode into a process already running under dcevm but our goal is to be able to reload the bytecode from an already running process just by attaching our own decompiler possibly with the agent.

I would like to ask a few questions:

1) what are the limitations when running with the agent but without dcevm? Any version range or unavailability of something?

2) As we are operating without a proper classpath, is it possible to register classes (as in autoHotswap=true) on runtime rather than when the program is executed?

3) Finally, i am not sure whether there are any dcevm developers here but if so:

a) have you tried to backport your changes into the upstream (openjdk project)?
b) if so, why has it not been accepted even as a build-time conditional flag?

[Jiri Bubnik]

Hi,

1) DCEVM extends standard Java Hotswap mechanism. In standard Java it is basically limited to changes in method body.

2) Yes, the plugin can load classes from any location.

3) https://github.com/dcevm/dcevm/issues/131

Kind Regards,

Jiri

Dne čtvrtek 8. července 2021 v 18:11:08 UTC+2 uživatel mko...@redhat.com napsal: